i think most of the people have the right idea on here, 26 for out of the US, no disc brakes either from what i've heard.

i prefer the feel of 700c, but my next ride will probably be a 54 trucker, with 26 rims, i guess they just feel like they have less momentum, something is different, but maybe it's just because i associate 26 inches with a larger tire : / either way, i suppose in the end it doesn't make a world of difference.